1 /* 2 * Copyright (c) 2002 Mark Santcroos <marks@ripe.net> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 * 24 * Netgraph "device" node 25 * 26 * This node presents a /dev/ngd%d device that interfaces to an other 27 * netgraph node. 28 * 29 * $FreeBSD$ 30 * 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/mbuf.h> 37 #include <sys/uio.h> 38 #include <sys/queue.h> 39 #include <sys/malloc.h> 40 #include <sys/conf.h> 41 #include <sys/poll.h> 42 #include <sys/ioccom.h> 43 44 #include <netgraph/ng_message.h> 45 #include <netgraph/netgraph.h> 46 47 #include "ng_device.h" 48 49 /* turn this on for verbose messages */ 50 #define NGD_DEBUG 51 52 /* Netgraph methods */ 53 static ng_constructor_t ng_device_cons; 54 static ng_rcvmsg_t ng_device_rcvmsg; 55 static ng_newhook_t ng_device_newhook; 56 static ng_connect_t ng_device_connect; 57 static ng_rcvdata_t ng_device_rcvdata; 58 static ng_disconnect_t ng_device_disconnect; 59 static int ng_device_mod_event(module_t mod, int event, void *data); 60 61 static int ng_device_init(void); 62 static int get_free_unit(void); 63 64 /* Netgraph type */ 65 static struct ng_type typestruct = { 66 .version = NG_ABI_VERSION, 67 .name = NG_DEVICE_NODE_TYPE, 68 .mod_event = ng_device_mod_event, 69 .constructor = ng_device_cons, 70 .rcvmsg = ng_device_rcvmsg, 71 .newhook = ng_device_newhook, 72 .connect = ng_device_connect, 73 .rcvdata = ng_device_rcvdata, 74 .disconnect = ng_device_disconnect, 75 }; 76 NETGRAPH_INIT(device, &typestruct); 77 78 /* per hook data */ 79 struct ngd_connection { 80 SLIST_ENTRY(ngd_connection) links; 81 82 struct cdev *ngddev; 83 struct ng_hook *active_hook; 84 char *readq; 85 int loc; 86 int unit; 87 }; 88 89 /* global data */ 90 struct ngd_softc { 91 SLIST_HEAD(, ngd_connection) head; 92 93 node_p node; 94 char nodename[NG_NODESIZ]; 95 } ngd_softc; 96 97 /* the per connection receiving queue maximum */ 98 #define NGD_QUEUE_SIZE (1024*10) 99 100 /* Maximum number of NGD devices */ 101 #define MAX_NGD 25 /* should be more than enough for now */ 102 103 static d_close_t ngdclose; 104 static d_open_t ngdopen; 105 static d_read_t ngdread; 106 static d_write_t ngdwrite; 107 static d_ioctl_t ngdioctl; 108 static d_poll_t ngdpoll; 109 110 static struct cdevsw ngd_cdevsw = { 111 .d_version = D_VERSION, 112 .d_flags = D_NEEDGIANT, 113 .d_open = ngdopen, 114 .d_close = ngdclose, 115 .d_read = ngdread, 116 .d_write = ngdwrite, 117 .d_ioctl = ngdioctl, 118 .d_poll = ngdpoll, 119 .d_name = "ngd", 120 }; 121 122 /* 123 * this holds all the stuff that should be done at load time 124 */ 125 static int 126 ng_device_mod_event(module_t mod, int event, void *data) 127 { 128 int error = 0; 129 130 #ifdef NGD_DEBUG 131 printf("%s()\n",__func__); 132 #endif /* NGD_DEBUG */ 133 134 switch (event) { 135 case MOD_LOAD: 136 137 ng_device_init(); 138 break; 139 140 case MOD_UNLOAD: 141 /* XXX do we need to do something specific ? */ 142 /* ng_device_breakdown */ 143 break; 144 145 default: 146 error = EOPNOTSUPP; 147 break; 148 } 149 150 return(error); 151 } 152 153 154 static int 155 ng_device_init() 156 { 157 struct ngd_softc *sc = &ngd_softc; 158 159 #ifdef NGD_DEBUG 160 printf("%s()\n",__func__); 161 #endif /* NGD_DEBUG */ 162 163 SLIST_INIT(&sc->head); 164 165 if (ng_make_node_common(&typestruct, &sc->node) != 0) { 166 printf("%s(): ng_make_node_common failed\n",__func__); 167 return(ENXIO); 168 } 169 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE); 170 if (ng_name_node(sc->node, sc->nodename)) { 171 NG_NODE_UNREF(sc->node); /* make it go away again */ 172 printf("%s(): ng_name_node failed\n",__func__); 173 return(ENXIO); 174 } 175 NG_NODE_SET_PRIVATE(sc->node, sc); 176 177 return(0); 178 } 179 180 /* 181 * don't allow to be created, only the device can do that 182 */ 183 static int 184 ng_device_cons(node_p node) 185 { 186 187 #ifdef NGD_DEBUG 188 printf("%s()\n",__func__); 189 #endif /* NGD_DEBUG */ 190 191 return(EINVAL); 192 } 193 194 /* 195 * Receive control message. We just bounce it back as a reply. 196 */ 197 static int 198 ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook) 199 { 200 struct ngd_softc *sc = &ngd_softc; 201 struct ng_mesg *msg; 202 int error = 0; 203 struct ngd_connection * connection = NULL; 204 struct ngd_connection *tmp = NULL; 205 206 #ifdef NGD_DEBUG 207 printf("%s()\n",__func__); 208 #endif /* NGD_DEBUG */ 209 210 NGI_GET_MSG(item, msg); 211 212 SLIST_FOREACH(tmp,&sc->head,links) { 213 if(tmp->active_hook == lasthook) { 214 connection = tmp; 215 } 216 } 217 if(connection == NULL) { 218 printf("%s(): connection is still NULL, no hook found\n",__func__); 219 return(-1); 220 } 221 222 return(error); 223 } 224 225 static int 226 get_free_unit() 227 { 228 struct ngd_connection *tmp = NULL; 229 struct ngd_softc *sc = &ngd_softc; 230 int n = 0; 231 int unit = -1; 232 233 #ifdef NGD_DEBUG 234 printf("%s()\n",__func__); 235 #endif /* NGD_DEBUG */ 236 237 /* When there is no list yet, the first device unit is always 0. */ 238 if SLIST_EMPTY(&sc->head) { 239 unit = 0; 240 return(unit); 241 } 242 243 /* Just do a brute force loop to find the first free unit that is 244 * smaller than MAX_NGD. 245 * Set MAX_NGD to a large value, doesn't impact performance. 246 */ 247 for(n = 0;n<MAX_NGD && unit == -1;n++) { 248 SLIST_FOREACH(tmp,&sc->head,links) { 249 250 if(tmp->unit == n) { 251 unit = -1; 252 break; 253 } 254 unit = n; 255 } 256 } 257 258 return(unit); 259 } 260 261 /* 262 * incoming hook 263 */ 264 static int 265 ng_device_newhook(node_p node, hook_p hook, const char *name) 266 { 267 struct ngd_softc *sc = &ngd_softc; 268 struct ngd_connection * new_connection = NULL; 269 270 #ifdef NGD_DEBUG 271 printf("%s()\n",__func__); 272 #endif /* NGD_DEBUG */ 273 274 new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT); 275 if(new_connection == NULL) { 276 printf("%s(): ERROR: new_connection == NULL\n",__func__); 277 return(-1); 278 } 279 280 new_connection->unit = get_free_unit(); 281 if(new_connection->unit<0) { 282 printf("%s: No free unit found by get_free_unit(), " 283 "increas MAX_NGD\n",__func__); 284 return(-1); 285 } 286 new_connection->ngddev = make_dev(&ngd_cdevsw, new_connection->unit, 0, 0,0600,"ngd%d",new_connection->unit); 287 if(new_connection->ngddev == NULL) { 288 printf("%s(): make_dev failed\n",__func__); 289 return(-1); 290 } 291 292 new_connection->readq = malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO); 293 if(new_connection->readq == NULL) { 294 printf("%s(): readq malloc failed\n",__func__); 295 return(-1); 296 } 297 298 /* point to begin of buffer */ 299 new_connection->loc = 0; 300 new_connection->active_hook = hook; 301 302 SLIST_INSERT_HEAD(&sc->head, new_connection, links); 303 304 return(0); 305 } 306 307 /* 308 * we gave ok to a new hook 309 * now connect 310 */ 311 static int 312 ng_device_connect(hook_p hook) 313 { 314 315 #ifdef NGD_DEBUG 316 printf("%s()\n",__func__); 317 #endif /* NGD_DEBUG */ 318 319 return(0); 320 } 321 322 323 /* 324 * Receive data from hook 325 */ 326 static int 327 ng_device_rcvdata(hook_p hook, item_p item) 328 { 329 struct mbuf *m; 330 struct ngd_softc *sc = &ngd_softc; 331 struct ngd_connection * connection = NULL; 332 struct ngd_connection * tmp; 333 char *buffer; 334 335 #ifdef NGD_DEBUG 336 printf("%s()\n",__func__); 337 #endif /* NGD_DEBUG */ 338 339 SLIST_FOREACH(tmp,&sc->head,links) { 340 if(tmp->active_hook == hook) { 341 connection = tmp; 342 } 343 } 344 if(connection == NULL) { 345 printf("%s(): connection is still NULL, no hook found\n",__func__); 346 return(-1); 347 } 348 349 NGI_GET_M(item, m); 350 NG_FREE_ITEM(item); 351 352 m = m_pullup(m,m->m_len); 353 if(m == NULL) { 354 printf("%s(): ERROR: m_pullup failed\n",__func__); 355 return(-1); 356 } 357 358 buffer = malloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO); 359 if(buffer == NULL) { 360 printf("%s(): ERROR: buffer malloc failed\n",__func__); 361 return(-1); 362 } 363 364 buffer = mtod(m,char *); 365 366 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) { 367 memcpy(connection->readq+connection->loc, buffer, m->m_len); 368 connection->loc += m->m_len; 369 } else 370 printf("%s(): queue full, first read out a bit\n",__func__); 371 372 free(buffer,M_DEVBUF); 373 374 return(0); 375 } 376 377 /* 378 * Removal of the last link destroys the node 379 */ 380 static int 381 ng_device_disconnect(hook_p hook) 382 { 383 struct ngd_softc *sc = &ngd_softc; 384 struct ngd_connection * connection = NULL; 385 struct ngd_connection * tmp; 386 387 #ifdef NGD_DEBUG 388 printf("%s()\n",__func__); 389 #endif /* NGD_DEBUG */ 390 391 SLIST_FOREACH(tmp,&sc->head,links) { 392 if(tmp->active_hook == hook) { 393 connection = tmp; 394 } 395 } 396 if(connection == NULL) { 397 printf("%s(): connection is still NULL, no hook found\n",__func__); 398 return(-1); 399 } 400 401 free(connection->readq,M_DEVBUF); 402 403 destroy_dev(connection->ngddev); 404 405 SLIST_REMOVE(&sc->head,connection,ngd_connection,links); 406 407 return(0); 408 } 409 /* 410 * the device is opened 411 */ 412 static int 413 ngdopen(struct cdev *dev, int flag, int mode, struct thread *td) 414 { 415 416 #ifdef NGD_DEBUG 417 printf("%s()\n",__func__); 418 #endif /* NGD_DEBUG */ 419 420 return(0); 421 } 422 423 /* 424 * the device is closed 425 */ 426 static int 427 ngdclose(struct cdev *dev, int flag, int mode, struct thread *td) 428 { 429 430 #ifdef NGD_DEBUG 431 printf("%s()\n",__func__); 432 #endif 433 434 return(0); 435 } 436 437 438 /* 439 * process ioctl 440 * 441 * they are translated into netgraph messages and passed on 442 * 443 */ 444 static int 445 ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td) 446 { 447 struct ngd_softc *sc = &ngd_softc; 448 struct ngd_connection * connection = NULL; 449 struct ngd_connection * tmp; 450 int error = 0; 451 struct ng_mesg *msg; 452 struct ngd_param_s * datap; 453 454 #ifdef NGD_DEBUG 455 printf("%s()\n",__func__); 456 #endif /* NGD_DEBUG */ 457 458 SLIST_FOREACH(tmp,&sc->head,links) { 459 if(tmp->ngddev == dev) { 460 connection = tmp; 461 } 462 } 463 if(connection == NULL) { 464 printf("%s(): connection is still NULL, no dev found\n",__func__); 465 return(-1); 466 } 467 468 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */ 469 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s), 470 M_NOWAIT); 471 if (msg == NULL) { 472 printf("%s(): msg == NULL\n",__func__); 473 goto nomsg; 474 } 475 476 /* pass the ioctl data into the ->data area */ 477 datap = (struct ngd_param_s *)msg->data; 478 datap->p = addr; 479 480 /* NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr) */ 481 NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, NULL); 482 if(error) 483 printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error); 484 485 nomsg: 486 487 return(0); 488 } 489 490 491 /* 492 * This function is called when a read(2) is done to our device. 493 * We pass the data available in kernelspace on into userland using 494 * uiomove. 495 */ 496 static int 497 ngdread(struct cdev *dev, struct uio *uio, int flag) 498 { 499 int ret = 0, amnt; 500 char buffer[uio->uio_resid+1]; 501 struct ngd_softc *sc = &ngd_softc; 502 struct ngd_connection * connection = NULL; 503 struct ngd_connection * tmp; 504 505 #ifdef NGD_DEBUG 506 printf("%s()\n",__func__); 507 #endif /* NGD_DEBUG */ 508 509 SLIST_FOREACH(tmp,&sc->head,links) { 510 if(tmp->ngddev == dev) { 511 connection = tmp; 512 } 513 } 514 if(connection == NULL) { 515 printf("%s(): connection is still NULL, no dev found\n",__func__); 516 return(-1); 517 } 518 519 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) { 520 amnt = MIN(uio->uio_resid,connection->loc); 521 522 memcpy(buffer,connection->readq, amnt); 523 memcpy(connection->readq, connection->readq+amnt, 524 connection->loc-amnt); 525 connection->loc -= amnt; 526 527 ret = uiomove((caddr_t)buffer, amnt, uio); 528 if(ret != 0) 529 goto error; 530 531 } 532 return(0); 533 534 error: 535 printf("%s(): uiomove returns error %d\n",__func__,ret); 536 /* do error cleanup here */ 537 return(ret); 538 } 539 540 541 /* 542 * This function is called when our device is written to. 543 * We read the data from userland into our local buffer and pass it on 544 * into the remote hook. 545 * 546 */ 547 static int 548 ngdwrite(struct cdev *dev, struct uio *uio, int flag) 549 { 550 int ret; 551 int error = 0; 552 struct mbuf *m; 553 char buffer[uio->uio_resid]; 554 int len = uio->uio_resid; 555 struct ngd_softc *sc =& ngd_softc; 556 struct ngd_connection * connection = NULL; 557 struct ngd_connection * tmp; 558 559 #ifdef NGD_DEBUG 560 printf("%s()\n",__func__); 561 #endif /* NGD_DEBUG */ 562 563 SLIST_FOREACH(tmp,&sc->head,links) { 564 if(tmp->ngddev == dev) { 565 connection = tmp; 566 } 567 } 568 569 if(connection == NULL) { 570 printf("%s(): connection is still NULL, no dev found\n",__func__); 571 return(-1); 572 } 573 574 if (len > 0) { 575 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0) 576 goto error; 577 } else 578 printf("%s(): len <= 0 : is this supposed to happen?!\n",__func__); 579 580 m = m_devget(buffer,len,0,NULL,NULL); 581 582 NG_SEND_DATA_ONLY(error,connection->active_hook,m); 583 584 return(0); 585 586 error: 587 /* do error cleanup here */ 588 printf("%s(): uiomove returned err: %d\n",__func__,ret); 589 590 return(ret); 591 } 592 593 /* 594 * we are being polled/selected 595 * check if there is data available for read 596 */ 597 static int 598 ngdpoll(struct cdev *dev, int events, struct thread *td) 599 { 600 int revents = 0; 601 struct ngd_softc *sc = &ngd_softc; 602 struct ngd_connection * connection = NULL; 603 struct ngd_connection * tmp; 604 605 606 if (events & (POLLIN | POLLRDNORM)) { 607 /* get the connection we have to know the loc from */ 608 SLIST_FOREACH(tmp,&sc->head,links) { 609 if(tmp->ngddev == dev) { 610 connection = tmp; 611 } 612 } 613 if(connection == NULL) { 614 printf("%s(): ERROR: connection is still NULL," 615 "no dev found\n",__func__); 616 return(-1); 617 } 618 619 if (connection->loc > 0) 620 revents |= events & (POLLIN | POLLRDNORM); 621 } 622 623 return(revents); 624 } 625